basic flask app python code example

Example 1: simple flask app

# Extremely simple flask application, will display 'Hello World!' on the screen when you run it
# Access it by running it, then going to whatever port its running on (It'll say which port it's running on).
from flask import Flask
app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello, World!'

if __name__ == '__main__':
    app.run()

Example 2: flask how to run app

$ export FLASK_APP=hello.py
$ python -m flask run
 * Running on http://127.0.0.1:5000/

Example 3: flask example

from flask import Flask
app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello, World!'

Example 4: basic flask app python

#Import Flask, if not then install and import.

import os
try:
  from flask import *
except:
  os.system("pip3 install flask")
  from flask import *

app = Flask(__name__)

@app.route("/")
def index():
  return "<h1>Hello World</h1>"

if __name__ == "__main__":
  app.run(host="0.0.0.0", port=8080, debug=False)

Example 5: flask tutorial

'''
use python and flask(one of the best web frameworks in python) 
as the server-side language and control the look of your web app 
using the front-end languages - html,css, and js...[TRY THE "MVC(model-visual-controlling)" METHOD]
'''
from flask import Flask, render_template #importing the module Flask and its attributes...

app = Flask(__name__)
@app.route('/')

def index():
  return render_template('index.html') #using the index.html file for visual controlling...


if __name__=="__main__":
  app.run()
  
'''
TODO:
<exremely important>
make sure that you :
	Create a new folder called "templates" in the same directory where your python file is saved ,and create a new html file called "index.html", and write your html code there...
    Store all assets and other files(including css files,images,videos,js files,and other html files{if any}) in the same "templates" folder...
'''